A large number of situations require monitoring of physical objects.
For example, a very widespread fear of travelers, regardless of their transportation means, is to lose or forget part of their luggage, or further having part of the latter stolen or substituted.
Presently, there are very few solutions for reassuring the traveler, and none of them is satisfactory in practice.
Labelling of the luggage for example is only efficient if a check of the association of the luggage and of their owner is permanently carried out, or at least continuously over particularly critical periods of time, such as the stopping of a train in a railway station, recovery of luggage after disembarking, or further passing security points. Such checks do not exist or at best they are random.
In fact, every time the traveler physically moves away from his luggage including when he/she places them in a compartment provided for this purpose somewhat distant from his/her seating position, he/she is at risk.
Continuous and systematic monitoring of luggage should be able to be set up simply, in particular without the traveler having to invest in complex protection devices.
It appears to be desirable that such monitoring may be provided as a service to a greater number of travelers, without however acquiring significant investments, in particular in equipment.
It is also indispensable that this monitoring shall not interfere with presently established security and checking devices, for example for discouraging terrorism.